Motor driven bidirectional pump and control circuit therefor



Sept. 25, 1956 E. P. M KEOWN 2,764,722

MOTOR DRIVEN BIDIRECTIONAL PUMP AND CONTROL CIRCUIT THEREFOR Filed Oct. 30, 1952 3 Sheets-Sheet 1 F 4 a! g 9 {Z WT J 1 {5 17 Edward P Ma [Goa/22 Sept. 25, 1956 E. P. M KEOWN 2,764,722

MOTOR DRIVEN BIDIRECTIONAL PUMP AND CONTROL CIRCUIT THEREFOR Filed Oct. 30, 1952 3 Sheets-Sheet 2 Edward" P McKeoa/z'z Iii-4. 5

Sept. 25, 1956 MCKEOWN 2,764,722

MOTOR DRIVEN BIDIREGTIONAL PUMP AND CONTROL CIRCUIT THEREFOR Filed Oct. 50, 1952 s Sheets-Sheet s Edward P Mcffmuzz United States Patent MOTOR DRIVEN BIDIRECTIONAL PUMP AND CONTROL CIRCUIT THEREFOR Edward P. McKeown, Benton Harbor, Mich., assignor,

by mesne assignments, to Whirlpool-Seeger Corporation, St. Joseph, Mich., a corporation of Delaware Application October 30, 1952, Serial No. 317,625

6 Claims. (Cl. 318-207) This invention relates to a motor reversing circuit and more particularly to a control circuit for use in conjunction with a bi-directional pump in an automatic laundering machine.

The present invention has particular application to automatic laundering machines where, for example, hot suds are pumped from the washing chamber into a reservoir during a first laundering cycle and are returned into the washing chamber at the beginning of a second laundering cycle. It is highly desirable to minimize the number of pumps, switches and other circuit components necessary for accomplishing this purpose.

It is, therefore, an important object of the present invention to provide a simple highly efiicient motor reversing circuit adapted for use in automatic laundering machines.

It is a further important object of the present invention to provide a circuit for accomplishing suds drain and suds return operations with the use of a single pump.

It is another important object of the present invention to provide a motor control circuit for reversing a motor upon the closure of a switch and for again reversing the motor upon opening of the switch.

Other objects and features of my invention will become evident to those skilled in the art through reference to the following detailed description and the appended drawings, in which I have described the manner of construction, organization and methods of operation of a preferred embodiment of my invention.

On the drawings:

Figure 1 is a top plan view of an automatic laundering machine and associated structures for accomplishing reuse of suds in successive laundering operations;

Figure 2 is a side elevational view of the structure of Figure 1;

Figure 3 is a schematic showing of a control circuit for the laundering machine of Figure 1; and

Figure 4 is a schematic showing of the motor control circuit portion of Figure 3 on an enlarged scale and in greater detail, the motor control circuit embodying the primary principles and teachings of the present invention.

Referring to Figures 1 and 2 of the drawings, an automatic laundering machine is illustrated comprising a tub T which defines a clothes laundering chamber and is supported by the support structure S. For withdrawing cleansing fluid from said tub to a suds reservoir 11 or drain basin 12, the tub is provided with a drain hose 13 connecting to one side of a bi-directional pump 14 driven by a reversible motor 15. The other side of the pump 14 is connected to a two-way valve 16. One branch of valve 16 connects through drain hose 17 with the drain basin 12, while the other branch connects through suds return hose 18 with the suds reservoir 11.

Thus in one direction of rotation of the motor 15, the pump is driven to pump hot suds water into reservoir 11 or rinse water into drain basin 12, while in the opposite direction of rotation of motor 15, the pump 14 will return the hot suds Water to the tub.

2,764,722 Patented Sept. 25, 1956 The diagram of Figure 3 represents the control circuit for the laundering machine of Figures v1 and 2. The circles numbered I through VII represent the timer cams driven by the timer motor 21. Thus the cams I-VII are rotated on a common shaft by motor 21 and at appropriate times initiate the various steps in the laundering operation.

The electric control circuit for automatic washing machines represented in Figure 3 and the detailed operation and construction of the machine are described in the Peter Eduard Geldhof application for patent entitled Automatic Laundering Machine and Pump Therefor, Serial No. 24,184, filed April 30, 1948, except for certain improvements which form the subject matter of the present invention. However, the environment of said improvements of the present invention can be sufficiently understood from the following general description of the control circuit of Figure 3.

With the timer cams I-VII set in fill position and the line switch 23 closed, and assuming that the temperature selector switch 35 is set so as to close both contacts 36-37 and 38-39, the washing chamber will be filled with water of an intermediate temperature. Cold water solenoid 42 is energized through the following circuit: supply conductor 20, contacts 43-44 of float switch 45, conductor 46, contacts 48-49 of switch 50 controlled by timer cam III, conductor 52, contacts 38-39 of switch 35, cold solenoid 42, and supply conductor 30.

The hot water solenoid 55 is similarly energized through the float valve 45, conductor 56, contacts 58-59 of switch 60 (associated with timer cam V) conductor 62, contacts 36-37 of switch 35, hot water solenoid 55, to supply conductor 30.

When the required amount of water passes into the tub, the liquid level control switch 45 disconnects contacts 43 and 44 and thereby causes fluid flow into the washing chamber to discontinue.

When contacts 43-44 of float switch 45 open, contacts 43-65 are closed to energize agitator solenoid 66 through the following circuit: supply conductor 20, contacts 43-65 of switch 45, conductor 68, contacts 70-71 of switch 72 (associated with timer cam VI), agitator solenoid 66, and supply conductor 30.

The motor 15 is started through the following circuit: supply conductor 20, contacts 43-65 of float switch 45, conductor 68, conductor 75, points 76 and .92 of three pole switch 80, point 93, start Winding 94 and switch 95 of motor 15, start coil 96 of relay 97, conductor 98, point 99, point 100, conductor 101 and supply conductor 30, and: from point 76 of three pole switch to point 77, running winding 105, conductor 106, hold coil 107, contacts 103-104 (closed by the starting circuit energization of start coil 96), and supply conductor 30.

When the motor comes up to normal speed, centrifugal switch 95 opens to cut out the starting winding 94.

Current flow through agitator solenoid 66 causes engagement of mechanical elements which drive the agitator in the tub T from the motor 15 to cause the agitator to execute oscillatory or reciprocating clothes washing movements. During this time, the timer motor 21 is energized through the following circuit to cause the operating cycle to progress: supply conductor 20, contacts 43, 65 of float switch 45, conductor 68, conductor 75, points 76 and 77 of three pole double throw switch 80, conductor 81, timer motor 21, conductor 82 and supply conductor 30.

At the end of the fill period, timer cams III and V operate to open contacts 48-49 of switch 50 and 58-59 of switch 60. In addition, switch is closed by timer cam 11 to render operation of timer motor 21, and pump motor 15 independent of float switch 45.

Upon completion of the wash period which may extend beyond the till period, a suds drain period follows. At this time, timer earn V1 opens switch '72 to deenergize the agitator solenoid 66. This causes the agitator to be mechanically disconnected from motor 15 to discontinue oscillating movements thereof and at the same time mechanically engages motor 15 and the bi-directional pump 14 to cause the latter to rotate in a direction to pump fluid out of tub T.

During the suds drain period, the two-Way valve solenoid 86 may be energized through the following circuit: supply conductor 29, contacts 4344 of iioat switch 45, conductor 44, conductor 46, contacts 48-37 of Switch 50 (associated with timer cum ill), conductor 88 and supply conductor 34 The solenoid $6 causes two-way valve 16 to connect the washing chamber with the storage reservoir it provided to hold the used washing suds. The motor 15 drives the bi-directional pump 14 in such a direction as to cause suds water to be pumped out of the washing chamber and into the storage reservoir.

During the last portion of the suds drain period, the extractor solenoid 117 is energized through the following circuit: supply conductor 26, contacts 43 float switch 45', conductor 44, conductor .iltl, contacts 111-112 of switch 115 (associated with timer cam I), conductor 116, extractor solenoid 117, conductor lit: and supply conductor 30.

The two-way valve solenoid 86 is now deenergized by timer cam III, contacts 4-387 of switch 50 opening. Two-Way valve 116 thus connects pump 14 to the drain basin 12. The clothes may then be sprayed with fresh water under the control of solenoid 42 to wash suds water off the clothes. The solenoid 42 may be energized through contacts 126127 of switch 125.

Toward the end of the extract suds period, timer cam ll opens switch 85, thereby disconnecting motor 15 from the source of energizing power since the float switch 45 is in the down position shown in Figure 3. Deenergization of motor 15 causes hold relay 97 to release armature 32 to open contacts lltl31il4. At this time, the time cam VII closes switch 125 to actuate cold water solenoid 42 through the following circuit: supply conductor 2d, contacts 43- 54 of fioat switch 45, conductor 110 (to the right), contacts l26ll27 of switch 125, conductor 128, cold solenoid 42, and supply conductor 30.

During this time, fresh rinse water flows into the washing chamber, and all other operations, including rotation of the timer cams by timer motor 21, are discontinued.

When the washing chamber fills, the float switch 45 closes contacts to energize timer motor 21 and motor 15 through conductor 63. The agitator solenoid 66 is then energized by timer cam VI closing switch 72. This causes the agitator in tub T to execute oscillating motions to rinse the clothes in the washing chamber thoroughly.

After the agitator rinse period, the drain rinse water period commences. Timer cam VI opens switch 72 to deenergize the agitator solenoid 66 to cause the agitator to be mechanically disconnected from the motor 15.

Deenergization of agitator solenoid 6-6 further causes the motor 15 to be mechanically engaged with the bidirectional pump 14 to rotate the pump in the direction to withdraw water from the washing chamber. Since the two-way valve solenoid 86 is not energized during this perieod, the interior of the washing chamber is in fluid communication wit the drain basin 12 through hose 13, pump 14, two-way valve 16, and drain hose 17, Figures 1 and 2.

After the rinse water drain period, the extract rinse water period is started. At this time, the timer cam I closes switch 115 and thereby energizes the extractor solenoid 117. This causes the motor l5 to engage the basket of the washing machine through a slip clutch which operates to limit the torque exerted on the drive mechanism. The basket is thereupon accelerated to a high rotational velocity and water is driven out of the clothes therein by the centrifugal forces associated with the rotational motion. The clothes may be sprayed with fresh water at the beginning of the extract rinse water period.

Upon completion of the extract rinse water period, the entire unit shuts off. The laundered clothes may then be removed from the unit.

When it is next desired to operate the machine, the cycle control switch may be placed at the suds return position. At this time, the suds return relay 13s is energized through the following circuit: supply conductor Ztl, conductor 131, contacts 13Z-l33 of switch 134, conductor 135, relay llfiil and supply conductor 38.

The two-way valve solenoid 86 is energized by timer cam HI closing contacts 4387 of switch 58.

Energization of suds return relay 13 as indicated in Figure 4, can es three pole double throw switch to move to its other position. Thus armature 137 is retracted by relay 130 against the action of spring 138 to move switch blade assembly All to its upper position. The motor starting circuit is now as follows with timer cam II having closed switch supply conductor 2d, conductor as, contacts 9tl-% of switch 85, conductor "75, points 76, 92 and 141, conductor 95 start portion 96 of relay 9'7, centrifugal switch 95', start winding 94, point 145, point loll, conductor 101 and supply conductor 30.

Thus, the start winding 94 is energized in the opposite direction and motor 15 operates in reverse during the suds return period to drive the bi-directional pump in such a direction as to return the used suds from the reservoir 11 to the washing chamber.

When the suds return is complete, timer cam 1V will open contacts l32133 of switch 134. At this time, the spring 133 is effective to shift the three pole switch blade assembly Mil to its lower position thus momentarily deenergizing the hold relay lit? to open contacts lt23l.tli.

The motor 15 then slows down, the centrifugal switch 95 eventually closing to connect starting winding 5% in the circuit. The motor will now begin to rotate in the proper direction for the removal of cleansing fluid from the tub during the new laundering operation.

While the circuit of Figure 4 has been described as it might be utilized in the circuit of an automatic laundering machine, it will be understood that the circuit has more general application. Generally, the circuit of Figure 4 operates to reverse a motor by means of solenoid 130, and the motor is restored to its forward direction of rotation simply by deenergization of the solenoid due to the temporary deenergization of hold coil lit? during movement of switch assembly Mil from its top position to its lower position. The centrifugal switch 95 closes as the motor slows down, and the start winding 94 is then energized in the opposite direction and the motor brought up to speed in the opposite direction. Thus, the closure of switch 134 (as by timer cam IV) is effective to reverse the direction of rotation of the motor, and opening of switch 134 again reverses the direction of rotation.

While I have resorted to detail in the description of my invention for the sake of clarity, it will, of course, be understood that many modifications with respect to various details will suggest themselves to those versed in the art which will not mark a departure from the true spirit of my invention. I desire to be limited, therefore, only by the scope of the appended claims and the prior art.

I claim as my invention:

1. In an automatic laundering machine, a tub, reversible pump means connected to' withdraw cleansing fluid from said tub and for returning cleansing fluid to said tub, reversible motor means for driving said pump including a running winding and a starting winding, relay means-including a start coil in series with said starting winding and a hold coil in series with said running winding, reversible switch means for connecting an energizing source in series with said starting winding and said start coil for starting said motor means selectively in opposite directions and for actuating said relay means, said relay means having contacts in series with said running winding for closure upon actuation of said relay means, second switch means for connecting an energizing source in series with said running winding and said hold coil and said contacts, whereby a holding circuit including said running winding and said hold coil maintains said contacts closed, means for disconnecting said start coil at a given :speed of said motor means, relay means for shifting said reversible switch means and momentarily interrupting :said holding circuit, and spring means opposing the action of said last mentioned relay means for again shifting said reversible switch means and momentarily interrupting :said holding circuit upon deenergization of said last mentioned relay means.

2. In an automatic laundering machine, a tub, reversible pump means connected to withdraw cleansing fluid from said tub and for returning cleansing fluid to said tub, reversible motor means for driving said pump including a running winding and a starting winding, a cyclic control thereof including a timer operated switch, relay means including a start coil in series with said starting winding and a hold coil in series with said running winding, a three pole double throw switch having a first pair of opposite contacts connected together and connected in series with said running winding, whereby shifting of said three pole double throw switch momentarily interrupts the circuit including said running winding and said hold coil, and having second and third pairs of opposite contacts cross connected and connected in series with said starting winding and said start coil whereby shifting of said three pole double throw switch reverses the connections to the circuit including said starting winding and said start coil, and electromagnet means energized upon closing of said timer operated switch for shifting said three pole double throw switch to reverse said motor means.

3. In an automatic laundering machine, a tub, reversible pump means connected to Withdraw cleansing fluid from said tub and for returning cleansing fluid to said tub, reversible motor means for driving said pump including a running winding and a starting winding, relay means including a start coil in series with said starting winding and a hold coil in series with said running winding, a three pole double throw switch having a first pair of opposite contacts connected together and connected in series with said running winding, whereby shifting of said switch momentarily interrupts the circuit including said running winding and said hold coil, and having second and third pairs of opposite contacts cross connected and connected in series with said starting winding and said start coil whereby shifting of said switch reverses the connections to the circuit including said starting winding and said start coil, relay means having an armature for shifting said switch from one switching position to the other switching position to reverse said motor means, and spring means opposing the action of said armature and for shifting said switch from said other switching position to said one switching position upon deenergization of said last mentioned relay means to again reverse said mOiZOI' means.

4. A control circuit for a reversible motor means having a running winding and a starting winding, comprising relay means including a start coil in series with said starting winding and a hold coil in series with said running winding, reversible switch means for connecting an energizin g source in series with said starting winding and said start coil for starting said motor means selectively in opposite directions and for actuating said relay means, said relay means having contacts in series with said running winding for closure upon actuation of said relay means, second switch means for connecting an energizing source in series with said running winding and said hold coil and said contacts, whereby a holding circuit including said running winding and said hold coil maintains said contacts closed, means for disconnecting said start coil at a given speed of said motor means, relay means for shifting said reversible switch means and for momentarily interrupting said holding circuit, and spring means opposing the action of said last mentioned relay means for again shifting said reversible switch means and momentarily interrupting said holding circuit upon deenergization of said last mentioned relay means.

5. A control circuit for reversible motor means having a running winding and a starting winding, comprising relay means including a start coil in series with said starting winding and a hold coil in series with said running winding, a three pole double throw switch having a first pair of opposite contacts connected together and connected in series with said running winding, whereby shifting of said switch momentarily interrupts the circuit including said running winding and said hold coil, and having second and third pairs of opposite contacts cross connected and connected in series with said starting winding and said start coil whereby shifting of said switch reverses the connections to the circuit including said starting winding and said start coil, and relay means having an armature for shifting said switch to reverse said motor means.

6. A control circuit for a reversible motor means having a running winding and a starting winding, comprising relay means including a start coil in series with said starting winding and a hold coil in series with said running winding, a three pole double throw switch having a first pair of opposite contacts connected together and connected in series with said running winding, whereby shifting of said switch momentarily interrupts the circuit including said running winding and said hold coil, and having second and third pairs of opposite contacts cross connected and connected in series with said starting winding and said start coil whereby shifting of said switch reverses the connections to the circuit including said starting winding and said start coil, relay means having an armature for shifting said switch from one switching position to the other switching position to reverse said motor means, and spring means opposing the action of said armature and for shifting said switch from said other switching position to said one switching position upon deenergization of said last mentioned relay means to again reverse said motor means.

References Cited in the file of this patent UNITED STATES PATENTS 2,334,965 Thacker Nov. 23, 1943 2,459,479 Weinland Jan. 18, 1949 2,594,657 Koonz Apr. 29, 1952 2,594,658 Koonz Apr. 29, 1952 

